Search results for "VASODILATION"
showing 10 items of 228 documents
Glucose-independent improvement of vascular dysfunction in experimental sepsis by dipeptidyl-peptidase 4 inhibition.
2012
Aims Dipeptidyl peptidase-4 (DPP-4) inhibitors are a novel class of drugs for the treatment of hyperglycaemia. Preliminary evidence suggests that their antioxidant and anti-inflammatory effects may have beneficial effects on the cardiovascular complications of diabetes. In the present study, we investigate in an experimental sepsis model whether linagliptin exerts pleiotropic vascular effects independent of its glucose-lowering properties. Methods and results Linagliptin (83 mg/kg chow for 7days) was administered in a rat model of lipopolysaccharide (LPS) (10 mg/kg, single i.p. dose/24 h)-induced sepsis. Vascular relaxation, reactive oxygen species (ROS) formation, expression of NADPH oxida…
The antifibrotic potential of a sustained release formulation of a PDGF beta-receptor targeted rho kinase inhibitor
2019
Rho kinase activity in hepatic stellate cells (HSCs) is associated with activation, transformation and contraction of these cells, leading to extracellular matrix production and portal hypertension in liver cirrhosis. Inhibition of rho kinase activity can reduce these activities, but may also lead to side effects, for instance systemic hypotension. This can be circumvented by liver-specific delivery of a rho kinase inhibitor to effector cells. Therefore, we targeted the rho kinase inhibitor Y27632 to the key pathogenic cells in liver fibrosis, i.e. myofibroblasts including activated HSCs that highly express the PDGF beta-receptor, using the drug carrier pPB-MSA. This carrier consists of mou…
Resveratrol: preventing properties against vascular alterations and ageing.
2005
International audience; Cardiovascular diseases are the leading cause of death in developed countries where the common pathological substrate underlying this process is atherosclerosis. Several new concepts have emerged in relation to mechanisms that contribute to the regulation of the vascular diseases and associated inflammatory effects. Recently, potential antioxidants (vitamin E, polyphenols) have received much attention as potential anti-atherosclerotic agents. Among the polyphenols with health benefic properties, resveratrol, a phytoalexin of grape, seem to be a good candidate protecting the vascular walls from oxidation, inflammation, platelet aggregation, and thrombus formation. In …
CD40L controls obesity-associated vascular inflammation, oxidative stress, and endothelial dysfunction in high fat diet-treated and db/db mice
2018
Abstract Aims CD40 ligand (CD40L) signaling controls vascular oxidative stress and related dysfunction in angiotensin-II-induced arterial hypertension by regulating vascular immune cell recruitment and platelet activation. Here we investigated the role of CD40L in experimental hyperlipidemia. Methods and results Male wild type and CD40L−/− mice (C57BL/6 background) were subjected to high fat diet for sixteen weeks. Weight, cholesterol, HDL, and LDL levels, endothelial function (isometric tension recording), oxidative stress (NADPH oxidase expression, dihydroethidium fluorescence) and inflammatory parameters (inducible nitric oxide synthase, interleukin-6 expression) were assessed. CD40L exp…
Potassium channels contribute to the increased sensitivity of the rabbit carotid artery to hydrogen sulfide in diabetes
2019
Abstract Hydrogen sulfide (H2S) is a potential endothelium-derived hyperpolarizing factor (EDHF) and adventitium- or adipocyte-derived relaxing factor (ADRF) which vasorelaxant action is mediated by potassium channels. H2S could also play an important role in the pathophysiology of diabetic cardiovascular complications. The present study has investigated the influence of alloxan-induced diabetes on the role of potassium channels mediating the relaxant response of the rabbit carotid artery to NaHS, a donor of H2S. NaHS (10−8-3 × 10−5 M) relaxed phenylephrine-precontracted carotid arteries, with higher potency in diabetic than in control rabbits. The selective blockers of potassium channels c…
Retinal arteriole reactivity in mice lacking the endothelial nitric oxide synthase (eNOS) gene
2018
Dysfunctional vascular endothelial nitric oxide synthase (eNOS) has been proposed to play a main pathophysiological role in various ocular diseases. The aim of the present study was to test the hypothesis that the chronic lack of eNOS impairs endothelium-dependent vasodilation in retinal arterioles. The relevance of eNOS for mediating vascular responses was studied in retinal vascular preparations from eNOS-deficient mice (eNOS-/-) and wild-type controls in vitro. Changes in luminal diameter in response to vasoactive agents were measured by videomicroscopy. The thromboxane mimetic, U46619, induced similar concentration-dependent constriction of retinal arterioles in eNOS-/- and wild-type mi…
Uncoupling of Endothelial Nitric Oxide Synthase in Perivascular Adipose Tissue of Diet-Induced Obese Mice
2015
Objective— The present study was conducted to investigate the contribution of perivascular adipose tissue (PVAT) to vascular dysfunction in a mouse model of diet-induced obesity. Approach and Results— Obesity was induced in male C57BL/6J mice with a high-fat diet for 20 weeks, and vascular function was studied with myograph. In PVAT-free aortas isolated from obese mice, the endothelium-dependent, nitric oxide–mediated vasodilator response to acetylcholine remained normal. In contrast, a clear reduction in the vasodilator response to acetylcholine was observed in aortas from obese mice when PVAT was left in place. Adipocytes in PVAT were clearly positive in endothelial nitric oxide synthase…
Chronic exercise impairs nitric oxide pathway in rabbit carotid and femoral arteries
2018
KEY POINTS: Some of the beneficial effects of exercise in preventing vascular related diseases are mediated by the enhancement of endothelial function where the role of nitric oxide (NO) is well documented, although the relevance of calcium activated potassium channels is not fully understood. The impact of oxidative stress induced by training on endothelial function remains to be clarified. By evaluating different endothelial vasodilator pathways on two vascular beds in a rabbit model of chronic exercise, we found a decreased NO bioavailability and endothelial nitric oxide synthase expression in both carotid and femoral arteries. Physical training induced carotid endothelial dysfunction as…
Chronic Administration of Quercetin Induces Biomechanical and Pharmacological Remodeling in the Rat Coronary Arteries
2017
Acute dilation brought about by the dietary flavonoid quercetin in coronary arterioles has been described earlier, but no information is available on its chronic effects. Male Wistar rats (body weight about 190 g) were divided to two groups: the quercetin-treated group (n=22) had quercetin supplementation of approximately 30 mg/kg/day, whereas the control group (n=20) had none. After eight weeks of treatment, intramural coronary arterioles with identical passive diameters (178+/-14 microm and 171+/-9 microm) were prepared and their biomechanics and pharmacological reactivities were tested using pressure arteriography ex vivo. The spontaneous tone of quercetin-treated arteries was higher (16…
Vasoactive properties of antihypertensive lactoferrin-derived peptides in resistance vessels: Effects in small mesenteric arteries from SHR rats
2017
Aims: Bovine lactoferrin (LF) hydrolysates and peptides identified thereof have shown antihypertensive effects in rat models, mainly but not exclusively by angiotensin-converting enzyme inhibition. In this study we aimed to assess the vasoactive effects and mechanisms of an ultrafiltered (< 3 kDa) pepsin LF hydrolysate (LFH) and a heptapeptide identified in a LF hydrolysate produced by yeast proteolysis (DPYKLRP) in peripheral resistance arteries from spontaneously hypertensive rats (SHRs). Main methods: We used a myograph system for isometric tension recording in isolated small mesenteric arteries from SHRs. Direct vasoactive effects of LFH (30–100 μg/mL) and DPYKLRP (30–100 μM) were asses…